Behavioral factors to modulate immunotherapy efficacy in cancer

Immune checkpoint inhibitors, including anti-PD-1 and anti-CTLA-4 therapies, are used to (re)activate the immune system to treat cancer. Despite promising results, a large group of patients does not respond to checkpoint inhibition. In the vulnerability-stress model of behavioral medicine, behavioral factors, such as stress, exercise and classical pharmacological conditioning, predict cancer incidence, recurrence and the efficacy of conventional cancer treatments. Given the important role of the immune system in these processes, certain behavior may be promising to complement immune checkpoint inhibition therapy. Here, we discuss the preliminary evidence and suitability of three behavioral mechanisms, i.e. stress modulation, exercise and classical pharmacological conditioning for the benefit of immunotherapy. It is crucial to study the potential beneficial effects of behavioral strategies that support immunotherapeutic anti-tumor effects with rigorous experimental evidence, to exploit behavioral mechanisms in improving checkpoint inhibition efficacy.

Interconnectivity between molecular subtypes and tumor stage in colorectal cancer

BACKGROUND

There are profound individual differences in clinical outcomes between colorectal cancers (CRCs) presenting with identical stage of disease. Molecular stratification, in conjunction with the traditional TNM staging, is a promising way to predict patient outcomes. We investigated the interconnectivity between tumor stage and tumor biology reflected by the Consensus Molecular Subtypes (CMSs) in CRC, and explored the possible value of these insights in patients with stage II colon cancer.

METHODS

We performed a retrospective analysis using clinical records and gene expression profiling in a meta-cohort of 1040 CRC patients. The interconnectivity of tumor biology and disease stage was assessed by investigating the association between CMSs and TNM classification. In order to validate the clinical applicability of our findings we employed a meta-cohort of 197 stage II colon cancers.

RESULTS

CMS4 was significantly more prevalent in advanced stages of disease (stage I 9.8% versus stage IV 38.5%, p < 0.001). The observed differential gene expression between cancer stages is at least partly explained by the biological differences as reflected by CMS subtypes. Gene signatures for stage III-IV and CMS4 were highly correlated (r = 0.77, p < 0.001). CMS4 cancers showed an increased progression rate to more advanced stages (CMS4 compared to CMS2: 1.25, 95% CI: 1.08-1.46). Patients with a CMS4 cancer had worse survival in the high-risk stage II tumors compared to the total stage II cohort (5-year DFS 41.7% versus 100.0%, p = 0.008).

CONCLUSIONS

Considerable interconnectivity between tumor biology and tumor stage in CRC exists. This implies that the TNM stage, in addition to the stage of progression, might also reflect distinct biological disease entities. These insights can potentially be utilized to optimize identification of high-risk stage II colon cancers.

Sire line of pigs affects weaning weight, growth performance, and carcass characteristics of offspring

Today, early weaning is more frequently applied by the modern pig breeder to obtain more litters per year. In addition, more and more European pig breeders apply a batch management system, which allows weaning to occur at fixed time points but entails that the offspring are treated at the litter level and not as individuals. Both evolutions might result in weaning lightweight piglets, which can cause, e.g., growth retardation of the offspring. Hence, the objective of this research was to improve the weaning weight of piglets of the same age by breeding with a highly conformed sire line. Therefore, a total of 23 sows were inseminated, 10 sows with semen of a well-conformed sire line (sire line B) and 13 sows with semen of a less conformed boar (sire line A). In total, 299 offspring were observed to monitor behavior, growth performance, and carcass characteristics. Subsequently, linear mixed models were developed to analyze the growth performance and carcass characteristics wherein only variables classified as significant ( < 0.05) were introduced as fixed factors. Results indicate that no significantly increased weaning weight could be accomplished by breeding with semen of sire line B. This could be due to the significant ( < 0.05) shorter gestation length of sows inseminated with semen of sire line B. However, the offspring of sire line B was defined by better carcass classification characteristics. Furthermore, this study presents that the mean birth weight of each piglet was significantly lower if a bigger litter size was recorded. When considering behavior, it was observed that piglets that did not seclude themselves from the litter had a significantly greater daily weight gain from birth to weaning compared to piglets that showed signs of isolation from the litter. A significantly greater daily gain from birth to slaughter was established for piglets with a greater birth weight. Also, results indicate that barrows had a significantly greater daily growth from weaning to slaughter than gilts. To conclude, this research determines that breeding with highly conformed sire lines does not improve the weaning weight of the offspring and thus cannot serve as a solution for early weaning. However, more research is required by performing more experiments with a greater number of boars and sows to confirm this result. In general, this study allows researchers to continue to improve and standardize the weaning weight of piglets of the same age.

Collagen-rich stroma in aggressive colon tumors induces mesenchymal gene expression and tumor cell invasion

Gene expression-based classification systems have identified an aggressive colon cancer subtype with mesenchymal features, possibly reflecting epithelial-to-mesenchymal transition (EMT) of tumor cells. However, stromal fibroblasts contribute extensively to the mesenchymal phenotype of aggressive colon tumors, challenging the notion of tumor EMT. To separately study the neoplastic and stromal compartments of colon tumors, we have generated a stroma gene filter (SGF). Comparative analysis of stroma^high and stroma^low tumors shows that the neoplastic cells in stroma^high tumors express specific EMT drivers (ZEB2, TWIST1, TWIST2) and that 98% of differentially expressed genes are strongly correlated with them. Analysis of differential gene expression between mesenchymal and epithelial cancer cell lines revealed that hepatocyte nuclear factor 4α (HNF4α), a transcriptional activator of intestinal (epithelial) differentiation, and its target genes are highly expressed in epithelial cancer cell lines. However, mesenchymal-type cancer cell lines expressed only part of the mesenchymal genes expressed by tumor-derived neoplastic cells, suggesting that external cues were lacking. We found that collagen-I dominates the extracellular matrix in aggressive colon cancer. Mimicking the tumor microenvironment by replacing laminin-rich Matrigel with collagen-I was sufficient to induce tumor-specific mesenchymal gene expression, suppression of HNF4α and its target genes, and collective tumor cell invasion of patient-derived colon tumor organoids. The data connect collagen-rich stroma to mesenchymal gene expression in neoplastic cells and to collective tumor cell invasion. Targeting the tumor-collagen interface may therefore be explored as a novel strategy in the treatment of aggressive colon cancer.

CFTR is a tumor suppressor gene in murine and human intestinal cancer

CFTR, the cystic fibrosis (CF) gene, encodes for the CFTR protein that plays an essential role in anion regulation and tissue homeostasis of various epithelia. In the gastrointestinal (GI) tract CFTR promotes chloride and bicarbonate secretion, playing an essential role in ion and acid-base homeostasis. Cftr has been identified as a candidate driver gene for colorectal cancer (CRC) in several Sleeping Beauty DNA transposon-based forward genetic screens in mice. Further, recent epidemiological and clinical studies indicate that CF patients are at high risk for developing tumors in the colon. To investigate the effects of CFTR dysregulation on GI cancer, we generated Apc(Min) mice that carried an intestinal-specific knockout of Cftr. Our results indicate that Cftr is a tumor suppressor gene in the intestinal tract as Cftr mutant mice developed significantly more tumors in the colon and the entire small intestine. In Apc(+/+) mice aged to ~1 year, Cftr deficiency alone caused the development of intestinal tumors in >60% of mice. Colon organoid formation was significantly increased in organoids created from Cftr mutant mice compared with wild-type controls, suggesting a potential role of Cftr in regulating the intestinal stem cell compartment. Microarray data from the Cftr-deficient colon and the small intestine identified dysregulated genes that belong to groups of immune response, ion channel, intestinal stem cell and other growth signaling regulators. These associated clusters of genes were confirmed by pathway analysis using Ingenuity Pathway Analysis and gene set enrichment analysis (GSEA). We also conducted RNA Seq analysis of tumors from Apc(+/+) Cftr knockout mice and identified sets of genes dysregulated in tumors including altered Wnt β-catenin target genes. Finally we analyzed expression of CFTR in early stage human CRC patients stratified by risk of recurrence and found that loss of expression of CFTR was significantly associated with poor disease-free survival.

Sound levels above 85 dB pre-slaughter influence pork quality

This study investigates whether sound levels above 85 dB(A), determined in literature as a critical sound level to induce stress in pigs, has also an effect on the pH of pork. Sound levels were recorded during pre-slaughter phases. A measure was taken after the arrival of the truck at the slaughterhouse, during unloading, lairage and just before stunning. The pH of the Longissimus thoracis or lumborum, 30 min after sticking (pH(30LT)) was measured. 8508 pigs were examined and the pH was measured on the carcasses. The results show that the cut-off value of 85 dB(A) during the pre-slaughtering phase is not only a threshold to evaluate animal welfare but can also be associated with a slower drop of pH if sound levels are b85 dB(A). Finally a linear mixed model for pH(30LT) was built with the sound level during lairage and the sound level prior to stunning as independent variables, having statistically the highest impact on pH(30LT) of pork.

Pre-slaughter handling and pork quality

Environmental variables, as sound levels, were collected during the pre-slaughter process in 18 different Belgian commercial slaughterhouses. Four pre-slaughter phases were determined: firstly after arrival of the truck at the slaughterhouse and just before unloading, secondly during unloading, thirdly at lairage and finally while moving to the stunner. A total of 8508 pigs was examined during the pre-slaughter process, of which the pH(LT) (M. longissimus thoracis), at 30 min post-mortem was measured. For each pre-slaughter phase, variables which might influence pork quality were determined. Moreover, this study made it possible to infer a checklist to represent and predict PSE traits of pork for all kind of pre-slaughter situations. The checklist shows also that the impact on pork quality is more decisive for the variables measured close to the stunning phase. Hence, this information is useful for the industry to optimize handling of pigs, reducing the risk for PSE traits.

Pre-slaughter rectal temperature as an indicator of pork meat quality

This study investigates whether rectal temperature of pigs, prior to slaughter, can give an indication of the risk of developing pork with PSE characteristics. A total of 1203 pigs were examined, measuring the rectal temperature just before stunning, of which 794 rectal temperatures were measured immediately after stunning. pH30LT (M. Longissimus thoracis) and temperature of the ham (Temp30Ham) were collected from about 530 carcasses, 30 min after sticking. The results present a significant positive linear correlation between rectal temperature just before and after slaughter, and Temp30Ham. Moreover, pH30LT is negatively correlated with rectal temperature and Temp30Ham. Finally, a linear mixed model for pH30LT was established with the rectal temperature of the pigs just before stunning and the lairage time. This model defines that measuring rectal temperature of pigs just before slaughter allows discovery of pork with PSE traits, taking into account pre-slaughter conditions.

[Echographic diagnosis of systolic murmur among 280 young French militaries. Implications for the expertise in military medicine]

Clinically discovering a systolic murmur is frequent among the young military population. When this murmur does not sound benign, a transthoracic echocardiography (TTE) is made to detect any cardiopathy, which could cause sudden cardiac death. The aim of this study was to evaluate the interest of systematic TTE in the assessment of any cardiac systolic murmur (CSM) among militaries.

METHODS

We ran a retrospective monocentric study in the "Clermont-Tonnerre" military hospital in Brest. We included all patients sent for TEE, aged 15 to 30 years old, from the 1st January 2010 until the 31st July 2013.

RESULTS

Two hundred and eighty TTES assessing CSM were performed. We found 28/280 (10%) echocardiographic abnormalities: 13 were bicuspid aortic valves (4.6%), 6 were ventricular septal defects (2.15%), 3 were atrial septal defects (1.07%), 4 were mild mitral regurgitations (1.43%), one mild pulmonary stenosis (0.35%) and one aortic stenosis (0.35%). No hypertrophic cardiomyopathy was found. Concerning military expertise, 11 (3.92%) patients among these 28 with abnormal TEE were considered unfit for work or "fit for work with limitations".

CONCLUSION

Assessing a cardiac systolic murmur with TEE lead to the diagnosis of a cardiomyopathy in 10% of the case. This study enhances the importance of systematic TEE when a CSM is detected in the young military, in order to determine if those soldiers can still fulfill their military duty.

Enamel pits in hamster molars, formed by a single high fluoride dose, are associated with a perturbation of transitional stage ameloblasts

Excessive intake of fluoride (F) by young children results in the formation of enamel subsurface porosities and pits, called enamel fluorosis. In this study, we used a single high dose of F administered to hamster pups to determine the stage of ameloblasts most affected by F and whether pit formation was related to F-related sub-ameloblastic cyst formation. Hamster pups received a single subcutaneous injection of either 20 mg or 40 mg NaF/kg body weight, were sacrificed 24 h later, and the number of cysts formed in the first molars were counted. Other pups were sacrificed 8 days after F injection, when the first molars had just erupted, to score for enamel defects. All F-injected pups formed enamel defects in the upper half of the cusps in a dose-dependent way. After injection of 20 mg NaF/kg, an average of 2.5 white spots per molar was found but no pits. At 40 mg NaF/kg, almost 4.5 spots per molar were counted as well as 2 pits per molar. The defects in erupted enamel were located in the upper half of the cusps, sites where cysts had formed at the transition stage of ameloblast differentiation. These results suggest that transitional ameloblasts, located between secretory- and maturation-stage ameloblasts, are most sensitive to the effects of a single high dose of F. F-induced cysts formed earlier at the pre-secretory stage were not correlated to either white spots or enamel pits, suggesting that damaged ameloblasts overlying a F-induced cyst regenerate and continue to form enamel.

[Cancer stem cells and future therapeutic implications]

A growing body of evidence indicates that a subpopulation of tumor cells, the so-called cancer stem cells (CSCs), drive tumor growth and metastasis and preclude therapy efficiency. CSCs have been isolated in virtually all type of tumors. These findings may have important consequences for clinical prognostic. Current cancer research aims to unravel the CSCs' unique biological mechanisms. The development of new CSCs-targeted treatments shed therefore new hopes in improving cancer therapy.

Crosstalk in inflammation: the interplay of glucocorticoid receptor-based mechanisms and kinases and phosphatases

Glucocorticoids (GCs) are steroidal ligands for the GC receptor (GR), which can function as a ligand-activated transcription factor. These steroidal ligands and derivatives thereof are the first line of treatment in a vast array of inflammatory diseases. However, due to the general surge of side effects associated with long-term use of GCs and the potential problem of GC resistance in some patients, the scientific world continues to search for a better understanding of the GC-mediated antiinflammatory mechanisms. The reversible phosphomodification of various mediators in the inflammatory process plays a key role in modulating and fine-tuning the sensitivity, longevity, and intensity of the inflammatory response. As such, the antiinflammatory GCs can modulate the activity and/or expression of various kinases and phosphatases, thus affecting the signaling efficacy toward the propagation of proinflammatory gene expression and proinflammatory gene mRNA stability. Conversely, phosphorylation of GR can affect GR ligand- and DNA-binding affinity, mobility, and cofactor recruitment, culminating in altered transactivation and transrepression capabilities of GR, and consequently leading to a modified antiinflammatory potential. Recently, new roles for kinases and phosphatases have been described in GR-based antiinflammatory mechanisms. Moreover, kinase inhibitors have become increasingly important as antiinflammatory tools, not only for research but also for therapeutic purposes. In light of these developments, we aim to illuminate the integrated interplay between GR signaling and its correlating kinases and phosphatases in the context of the clinically important combat of inflammation, giving attention to implications on GC-mediated side effects and therapy resistance.

The versatile role of MSKs in transcriptional regulation

Among the mitogen-activated protein kinase (MAPK) targets, MSKs (mitogen- and stress-activated protein kinases) comprise a particularly interesting protein family. Because MSKs can be activated by both extracellular-signal-regulated kinase and p38 MAPKs, they are activated by many physiological and pathological stimuli. About ten years after their original discovery, they have been recognized as versatile kinases regulating gene transcription at multiple levels. MSKs directly target transcription factors, such as cAMP-response-element-binding protein and nuclear factor-kappaB, thereby enhancing their transcriptional activity. They also induce histone phosphorylation, which is accompanied by chromatin relaxation and facilitated binding of additional regulatory proteins. Here, we review the current knowledge on MSK activation and its molecular targets, focusing on recent insights into the role of MSKs at multiple levels of transcriptional regulation.

Ser276 phosphorylation of NF-kB p65 by MSK1 controls SCF expression in inflammation

Transcription of the mast cell growth factor SCF (stem cell factor) is upregulated in inflammatory conditions, and this is dependent upon NF-κB, as well as the MAP kinases p38 and ERK activation. We show here that the MAPK downstream nuclear kinase MSK1 induces NF-κB p65 Ser276 phosphorylation upon IL-1ß treatment, which was inhibited in cells transfected with a MSK1 kinase-dead (KD) mutant compared to the WT control. In addition, we show by ChIP experiments that MSK1 as well as MAPK inhibition abolishes binding of p65, of its coactivator CBP, and of MSK1 itself to the κB intronic enhancer site of the SCF gene. We show that interaction between NF-κB and CBP is prevented in cells transfected by a p65 S276C mutant. Finally, we demonstrate that both transfections of MSK1-KD and MSK1 siRNA - but not the WT MSK1 or control siRNA - downregulate the expression of SCF induced by IL-1ß. Our study provides therefore a direct link between MSK1-mediated phosphorylation of Ser276 p65 of NF-κB, allowing its binding to the SCF intronic enhancer, and pathophysiological SCF expression in inflammation.

Glucocorticoids and mitogen- and stress-activated protein kinase 1 inhibitors: possible partners in the combat against inflammation

In the combat against inflammation, glucocorticoids (GCs) are a widespread therapeutic. These ligands of the glucocorticoid receptor (GR) inhibit the transactivation of various transcription factors, including nuclear factor-kappaB (NF-kappaB), and alter the composition of the pro-inflammatory enhanceosome, culminating in the repression of pro-inflammatory gene expression. However, pharmacological usage of GCs in long-term treatment is burdened with a detrimental side-effect profile. Recently, we discovered that GCs can lower NF-kappaB transactivation and pro-inflammatory gene expression by abolishing the recruitment of mitogen- and stress-activated protein kinase 1 (MSK1) (EC 2.7.11.1) to pro-inflammatory gene promoters and displacing a significant fraction of MSK1 to the cytoplasm. In our current investigation in L929sA fibroblasts, upon combining GCs and MSK1 inhibitors, we discovered a dose-dependent additive repression of pro-inflammatory gene expression, most likely due to diverse and multilayered repression mechanisms employed by GCs and MSK1 inhibitors. Therefore, the combined application of GCs and MSK1 inhibitors enabled a similar level of repression of pro-inflammatory gene expression, using actually a lower concentration of GCs and MSK1 inhibitors combined than would be necessary when using these inhibitors separately. Although H89 can inhibit both MSK1 and PKA, TNF does not activate PKA (EC 2.7.11.11) and as such PKA inhibition does not mediate H89-instigated repression of TNF-stimulated gene expression. Furthermore, the additional repressive effects of liganded GR and inhibition of MSK1, are not mediated via GR transactivation mechanisms. In conclusion, these results could entail a new therapeutic strategy using lower drug concentrations, potentially leading to a more beneficial side-effect profile.

Involvement of GSK-3β in TWEAK-mediated NF-κB activation

Glycogen synthase kinase-3beta (GSK-3beta) is a key component of several signaling pathways. We found that a short variant of 'TNF-like weak inducer of apoptosis' (shortTWEAK) formed a complex with GSK-3beta in a yeast two-hybrid system. We demonstrate that shortTWEAK and GSK-3beta colocalize in the nucleus of human neuroblastoma cells. We also show that TWEAK is internalized in different cell lines and that it translocates to the nucleus. This event causes the degradation of IkappaBalpha, the nuclear translocation of both GSK-3beta and p65, and the induction of NF-kappaB-driven gene expression. We demonstrate that the induction of IL-8 expression by TWEAK can be counteracted by LiCl. Taken together, these data suggest that GSK-3beta plays an important role in the signal transduction pathway between TWEAK and NF-kappaB.

Altered subcellular distribution of MSK1 induced by glucocorticoids contributes to NF-kappaB inhibition

Glucocorticoids are widely used anti-inflammatory and immunomodulatory agents, of which the action mechanism is mainly based on interference of hormone-activated glucocorticoid receptor (GR) with the activity of transcription factors, such as nuclear factor-kappaB (NF-kappaB). In addition to the well described interaction-based mutual repression mechanism between the GR and NF-kappaB, additional mechanisms are at play, which help to explain the efficacy of glucocorticoid-mediated gene repression. In this respect, we found that glucocorticoids counteract the recruitment of activated Mitogen- and Stress-activated protein Kinase-1 (MSK1) at inflammatory gene promoters resulting in the inhibition of NF-kappaB p65 transactivation and of concurrent histone H3 phosphorylation. Additionally, we observed that activated GR can trigger redistribution of nuclear MSK1 to the cytoplasm through a CRM1-dependent export mechanism, as a result of an interaction between liganded GR and activated MSK1. These findings unveil a novel aspect within the GR-mediated NF-kappaB-targeting anti-inflammatory mechanism.

Cancer stem cells--old concepts, new insights

Cancer has long been viewed as an exclusively genetic disorder. The model of carcinogenesis, postulated by Nowell and Vogelstein, describes the formation of a tumor by the sequential accumulation of mutations in oncogenes and tumor suppressor genes. In this model, tumors are thought to consist of a heterogeneous population of cells that continue to acquire new mutations, resulting in a highly dynamic process, with clones that out compete others due to increased proliferative or survival capacity. However, novel insights in cancer stem cell research suggest another layer of complexity in the process of malignant transformation and preservation. It has been reported that only a small fraction of the cancer cells in a malignancy have the capacity to propagate the tumor upon transplantation into immuno-compromised mice. Those cells are termed 'cancer stem cells' (CSC) and can be selected based on the expression of cell surface markers associated with immature cell types. In this review, we will critically discuss these novel insights in CSC-related research. Where possible we integrate these results within the genetic model of cancer and illustrate that the CSC model can be considered an extension of the classic genetic model rather than a contradictory theory. Finally, we discuss some of the most controversial issues in this field.

Histone Deacetylase Inhibitor Trichostatin A Sustains Sodium Pervanadate-induced NF-κB Activation by Delaying IκBα mRNA Resynthesis

NF-kappaB is a crucial transcription factor tightly regulated by protein interactions and post-translational modifications, like phosphorylation and acetylation. A previous study has shown that trichostatin A (TSA), a histone deacetylase inhibitor, potentiates tumor necrosis factor (TNF) alpha-elicited NF-kappaB activation and delays IkappaBalpha cytoplasmic reappearance. Here, we demonstrated that TSA also prolongs NF-kappaB activation when induced by the insulino-mimetic pervanadate (PV), a tyrosine phosphatase inhibitor that initiates an atypical NF-kappaB signaling. This extension is similarly correlated with delayed IkappaBalpha cytoplasmic reappearance. However, whereas TSA causes a prolonged IKK activity when added to TNFalpha, it does not when added to PV. Instead, quantitative reverse transcriptase-PCR revealed a decrease of ikappabalpha mRNA level after TSA addition to PV stimulation. This synthesis deficit of the inhibitor could explain the sustained NF-kappaB residence in the nucleus. In vivo analysis by chromatin immunoprecipitation assays uncovered that, for PV induction but not for TNFalpha, the presence of TSA provokes several impairments on the ikappabalpha promoter: (i) diminution of RNA Pol II recruitment; (ii) reduced acetylation and phosphorylation of histone H3-Lys(14) and -Ser(10), respectively; (iii) decreased presence of phosphorylated p65-Ser(536); and (iv) reduction of IKKalpha binding. The recruitment of these proteins on the icam-1 promoter, another NF-kappaB-regulated gene, is not equally affected, suggesting a promoter specificity of PV with TSA stimulation. Taken together, these data suggest that TSA acts differently depending on the NF-kappaB pathway and the targeted promoter in question. This indicates that one overall histone deacetylase role is to inhibit NF-kappaB activation by molecular mechanisms specific of the stimulus and the promoter.

Attenuation of mitogen- and stress-activated protein kinase-1-driven nuclear factor-kappaB gene expression by soy isoflavones does not require estrogenic activity

We have analyzed in molecular detail how soy isoflavones (genistein, daidzein, and biochanin A) suppress nuclear factor-kappaB (NF-kappaB)-driven interleukin-6 (IL6) expression. In addition to its physiologic immune function as an acute stress cytokine, sustained elevated expression levels of IL6 promote chronic inflammatory disorders, aging frailty, and tumorigenesis. Our results in estrogen-unresponsive fibroblasts, mitogen- and stress-activated protein kinase (MSK) knockout cells, and estrogen receptor (ER)-deficient breast tumor cells show that phytoestrogenic isoflavones can selectively block nuclear NF-kappaB transactivation of specific target genes (in particular IL6), independently of their estrogenic activity. This occurs via attenuation of mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase (MEK) and ERK activity, which further down-regulates MSK-dependent NF-kappaB p65 and histone H3 phosphorylation. As constitutive NF-kappaB and MSK activity are hallmarks of aggressive metastatic ER-deficient breast cancer, the MSK signaling pathway may become an attractive target for chemotherapy.

Regulation of NF-kappaB transcriptional activity

Nuclear factor kappaB (NF-kappaB) is regarded as a key regulator of inflammation; hence, several inflammatory diseases result from deregulation of NF-kappaB signaling. There is, however, also increasing evidence for a preponderant role of NF-kappaB in tumor development and progression. Constitutive activation of NF-kappaB activity by signaling defects, mutations or chromosomal rearrangements can be found in a wide variety of cancers. Additionally, a causal link between inflammation and cancer has been noted, which makes NF-kappaB an interesting target for development of both anti-inflammatory and anti-cancer therapeutics. Here, we review current knowledge of NF-kappaB signal transduction, focusing on the regulation of its transcriptional activity by post-translational modification of the NF-kappaB subunits.

Role of CREB1 and NFκB-p65 in the Down-regulation of Renin Gene Expression by Tumor Necrosis Factor α

Tumor necrosis factor-alpha (TNFalpha) is a potent inhibitor of renin gene expression in renal juxtaglomerular cells. We have found that TNFalpha suppresses renin transcription via transcription factor NFkappaB, which targets a cAMP responsive element (CRE) in the renin promoter. Here we aimed to further clarify the role of NFkappaB and the canonical CRE-binding proteins of the CRE-binding protein/activating transcription factor (CREB/ATF) family in the inhibition of renin gene expression by TNFalpha in the juxtaglomerular cell line As4.1. TNFalpha caused a moderate decrease in the binding of CREB1 to its cognate CRE DNA binding site. On the other hand, NFkappaB-p65 transcriptional activity was substantially reduced by TNFalpha, which targeted a trans-activation domain at the very C terminus of the p65 molecule. Our results suggest that TNFalpha inhibits renin gene expression by decreasing the transactivating capacity of NFkappaB-p65 and partially by attenuating CREB1 binding to CRE.

Medroxyprogesterone acetate downregulates cytokine gene expression in mouse fibroblast cells

Although medroxyprogesterone acetate (MPA) is used as an injectable contraceptive, in hormone replacement therapy (HRT) and in treatment of certain cancers, the steroid receptors and their target genes involved in the actions of MPA are not well understood. We show that MPA, like dexamethasone (dex), significantly represses tumour necrosis factor (TNF)-stimulated interleukin-6 (IL-6) protein production in mouse fibroblast (L929sA) cells. In addition, MPA repressed IL-6 and IL-8 promoter-reporter constructs at the transcriptional level, via interference with nuclear factor kappaB (NFkappaB) and activator protein-1 (AP-1). Furthermore, like dex, MPA does not affect NFkappaB DNA-binding activity. We also observed significant transactivation by MPA of a glucocorticoid response element (GRE)-driven promoter-reporter construct in both L929sA and COS-1 cells. The MPA-induced nuclear translocation of the glucocorticoid receptor (GR), as well as the antagonistic effects of RU486, strongly suggest that the actions of MPA in these cells are mediated at least in part via the GR.

Transcriptional activation of the NF-kappaB p65 subunit by mitogen- and stress-activated protein kinase-1 (MSK1)

Nuclear factor kappaB (NF-kappaB) is one of the key regulators of transcription of a variety of genes involved in immune and inflammatory responses. NF-kappaB activity has long been thought to be regulated mainly by IkappaB family members, which keep the transcription factor complex in an inactive form in the cytoplasm by masking the nuclear localization signal. Nowadays, the importance of additional mechanisms controlling the nuclear transcription potential of NF-kappaB is generally accepted. We show that the mitogen-activated protein kinase inhibitors SB203580 and PD98059 or U0126, as well as a potent mitogen- and stress- activated protein kinase-1 (MSK1) inhibitor H89, counteract tumor necrosis factor (TNF)-mediated stimulation of p65 transactivation capacity. Mutational analysis of p65 revealed Ser276 as a target for phosphorylation and transactivation in response to TNF. Moreover, we identified MSK1 as a nuclear kinase for p65, since MSK1 associates with p65 in a stimulus-dependent way and phosphorylates p65 at Ser276. This effect represents, together with phosphorylation of nucleosome components such as histone H3, an essential step leading to selective transcriptional activation of NF-kappaB-dependent gene expression.

A Paradigm for Gene Regulation: Inflammation, NF-κB and PPAR

The onset of inflammatory gene expression is driven by the transcription factor NF-kappaB, whose transcriptional activity is regulated at multiple levels. First, NF-kappaB activity is regulated by cytoplasmic degradation of the IkappaB inhibitor and nuclear translocation. Second, the nuclear p65 transactivation potential can be further influenced by posttranslational modifications, such as phosphorylation and/or acetylation. The p65 phosphorylation is a process highly regulated by both cell- and stimulus-dependent activating kinases. Ser276 phosphorylation seems to be highly important considering its crucial role in the interaction with and the engagement of the cofactor CBP/p300. We have identified MSK1 as an acting kinase in the TNF-signalling pathway, where it is responsible for p65 phosphorylation at Ser276, as well as for H3 phosphorylation of Ser10 in IL-6 promoter-associated chromatin (Fig. 1) (Saccani et al., 2002; Vermeulen et al., 2002, 2003). To our knowledge, this was the first report that identifies one particular kinase involved in transcription factor phosphorylation and histone modification at the level of a single promoter in order to establish gene activation. The question of which element takes the initial step to recruit and to assemble the activated transcription complex still remains unanswered (Vanden Berghe et al., 2002). PPAR alpha negatively interferes with inflammatory gene expression by up-regulation of the cytoplasmic inhibitor molecule IkappaB alpha, thus establishing an autoregulatory loop (Fig. 1). This induction takes place in the absence of a PPRE, but requires the presence of NF-kappaB and Sp1 elements in the IkappaB alpha promoter sequence as well as DRIP250 cofactors. The detailed mechanism how PPAR can activate genes in a non-DNA-binding way needs further investigation; moreover, it is at present not clear whether this upregulation, unlike the inhibitory effect of glucocorticoids, is a cell type- or a PPAR-specific phenomenon.

Regulation of the transcriptional activity of the nuclear factor-kappaB p65 subunit

Nuclear factor-kappaB (NF-kappaB) is well known for its role in inflammation, immune response, control of cell division and apoptosis. The function of NF-kappaB is primarily regulated by IkappaB family members, which ensure cytoplasmic localisation of the transcription factor in the resting state. Upon stimulus-induced IkappaB degradation, the NF-kappaB complexes move to the nucleus and activate NF-kappaB-dependent transcription. Over the years, a second regulatory mechanism, independent of IkappaB, has become generally accepted. Changes in NF-kappaB transcriptional activity have been assigned to phosphorylation of the p65 subunit by a large variety of kinases in response to different stimuli. Here, we give an overview of the kinases and signalling pathways mediating this process and comment on the players involved in tumour necrosis factor-induced regulation of NF-kappaB transcriptional activity. Additionally, we describe how other posttranslational modifications, such as acetylation and methylation of transcription factors or of the chromatin environment, may also affect NF-kappaB transcriptional activity.

Assessing the quality of life in children with cystic fibrosis

Although patients with cystic fibrosis (CF) are experiencing increased longevity, it is unclear that improved quality of life (QoL) accompanies the greater quantity of life. This is especially true of children with CF where the burdens of treatment are substantial. Assessing QoL in such children is difficult, and only one instrument--the Quality of Well-Being (QWB) scale--seems to have been used extensively to assess QoL in children with CF. After thoroughly reviewing the literature, we surveyed the 113 certified CF centers in the United States about QoL assessment. With 84% responding, it was found that only 7 centers are assessing QoL--4 have been using the QWB instrument. Concurrently, we pilot tested the QWB instrument in children being followed longitudinally in the Wisconsin CF Neonatal Screening Project. Our results indicated that QWB scores reflecting QoL decreased as the number of respiratory infections increased, as the number of concurrent medical conditions increased, and as the number of different medications increased. However, we recognized problems with the assessed domains and data interpretation. In fact, the QWB instrument has limited sensitivity and responds more to the extent of physician-determined treatment than to QoL. There is a need for more QoL assessment and better instruments, particularly in young children with CF.

Signal transduction by tumor necrosis factor and gene regulation of the inflammatory cytokine interleukin-6

Interleukin (IL)-6 is a multifunctional cytokine that can be induced by a plethora of chemical or physiological compounds, including the inflammatory cytokines tumor necrosis factor (TNF) and IL-1. The molecule TNF has a trimeric configuration and thus binds to membrane-bound, cellular receptors to initiate cell death mechanisms and signaling pathways leading to gene induction. Previously, we showed that induced clustering of the intracellular domains of the p55 TNF receptor, or of their respective 'death domains' only, is sufficient to activate the nuclear factor kappa B (NF-kappa B) and several mitogen-activated protein kinase (MAPK) pathways. NF-kappa B is the exclusive transcription factor for induction of the IL-6 gene in response to TNF and functions as the final trigger to activate a multiprotein complex, a so-called 'enhanceosome', at the level of the IL-6 promoter. Furthermore, the enhanceosome displays histone acetylation activity, which turned out to be essential for IL-6 gene activation via NF-kappa B. However, activation of NF-kappa B alone is not sufficient for IL-6 gene induction in response to TNF, as inhibition of the coactivated extracellular signal-regulated kinase and p38 MAPK pathways blocks TNF-mediated gene expression. Nevertheless, the transactivating NF-kappa B subunit p65 is not a direct target of MAPK phosphorylation. Thus, we postulated that other components of the enhanceosome complex are sensitive to MAPK cascades and found that MAPK activity is unequivocally linked to the histone acetylation capacity of the enhanceosome to stimulate gene expression in response to TNF. In contrast, glucocorticoid repression of TNF-driven IL-6 gene expression does not depend on abrogation of histone acetyltransferase activity, but originates from interference of the liganded glucocorticoid receptor with the contacts between NF-kappa B p65 and the promoter configuration around the TATA box.

Activity and dosage of alteplase dilution for clearing occlusions of venous-access devices

The activity and sterility of reconstituted alteplase solution and the effectiveness of an alteplase dose-escalation protocol for the clearance of midline-catheter and central-venous-access device occlusions were studied. Reconstituted alteplase solution was stored at -70, -25, or 2 degrees C at concentrations of 0.5, 1, or 2 mg/mL. Durations of storage in the freezer were 0, 7, and 14 days, and durations of storage in the refrigerator were 0, 48, and 72 hours and 7 and 14 days. Samples were also assayed and cultured without prior freezing after refrigeration at 2 degrees C for 0, 48, and 72 hours and 7, 14, and 28 days. Fifty-eight pediatric and adult patients were enrolled in a separate study in which catheter clearance was initiated with alteplase 0.5 mg, and the dose was escalated to 1 and 2 mg sequentially until the catheter was cleared. The primary endpoint was restoration of catheter patency, and the secondary endpoint was the occurrence of bleeding episodes within 24 hours of alteplase administration. Catheter removal due to failure to restore patency was also documented. The activity and sterility of alteplase were maintained under all conditions studied. Fifty catheters (86.2%) were cleared with alteplase 0.5 mg, 5 (8.6%) after dose escalation to 1 mg, and 1 (1.7%) after escalation to 2 mg. The alteplase solution did not clear the occlusion in 2 catheters (3.4%): 1 had a mechanical obstruction and 1 cleared two hours after the 1-mg dose was deemed a failure. None of the six catheter removals was due to recalcitrant clots. Bleeding observed was not considered to be the result of alteplase administration. For use in clearing occlusions of venous-access devices, alteplase 0.5, 1, and 2 mg/mL retained sufficient fibrinolytic activity when stored for up to 14 days at 2 degrees C (28 days for the 0.5-mg/mL dilution) and when stored for 14 days at -70 or -25 degrees C followed by up to 14 days at 2 degrees C. The dose-escalation protocol was effective.

Glucocorticoids repress NF-kappaB-driven genes by disturbing the interaction of p65 with the basal transcription machinery, irrespective of coactivator levels in the cell

Glucocorticoids (GCs) are used to combat inflammatory diseases. Their beneficial effect relies mainly on the inhibition of NF-kappaB- and/or AP-1-driven proinflammatory gene expression. Previously, we have shown that GCs repress tumor necrosis factor-induced IL-6 gene expression by an NF-kappaB-dependent nuclear mechanism without changing the DNA-binding capacity of NF-kappaB or the expression levels of the cytoplasmic inhibitor of NF-kappaB (IkappaB-alpha). In the present work, we investigate the effect of GC repression on different natural and/or recombinant NF-kappaB-driven reporter gene constructs in the presence of increasing amounts of various coactivator molecules, such as CREB-binding protein (CBP), p300, and SRC-1. We found that GCs maintain their repressive capacities, irrespective of the amount of cofactor present in the cell. Similar results were obtained for the reciprocal transrepression of a GC receptor (GR) element-driven reporter gene by p65. We demonstrate that neither the expression levels of p65 and CBP nor their physical association are affected by activated GR. Using Gal4 chimeras, we show that repression by GCs is specific for p65-mediated transactivation, ruling out competition for limiting nuclear factors as the major underlying mechanism of gene repression. In addition, the transactivation potential of a point-mutated Gal4-p65 variant with a decreased CBP interaction capability is still repressed by GR. Finally, we present evidence that the specificity of GC repression on p65-driven gene expression is codetermined by the TATA box context.

Factors determining the place of palliative care and death of cancer patients

Factors determining the place of palliative care and death were studied by interviewing 40 patients using a semi-structured questionnaire. The 86 interviews assessed showed that both emotional and somatic factors played a part in the determination of whether patients were transferred and of their place of death. Emotional factors were mentioned in 41% as being of importance, and physical factors in 32%. Material and financial factors are probably underestimated owing to the methodology.

Enzymatic properties of rat group IIA and V phospholipases A(2) compared

Group IIA and V phospholipases A(2) (PLA(2)s) are known to play a role in inflammatory responses. We have constructed a bacterial expression vector for rat group IIA and V PLA(2)s, over-expressed, folded and purified the proteins with the aim to study and compare the properties of the enzymes in detail. For zwitterionic phospholipid micelles, both enzymes display optimum activity at pH 8. 0 and absolutely require Ca(2+) for enzymatic activity. In the presence of substrate, group V PLA(2) has a high affinity for Ca(2+) (K(Ca2+)=90 microM) while K(Ca2+) of group IIA PLA(2) was found to be 1.6 mM. The absence of substrate only marginally influences the Ca(2+) affinities. In contrast to group IIA PLA(2), group V PLA(2) does not show a jump in the activity profile at substrate concentrations around the critical micelle concentration. Direct binding studies using n-alkylphosphocholines indicate that group V PLA(2) forms protein-lipid aggregates at pre-micellar lipid concentrations in a cooperative and Ca(2+)-dependent manner. This behavior, which is comparable to that observed for the PLA(2) from Naja melanoleuca snake venom, reflects the high affinity of this enzyme for zwitterionic phospholipids. Competitive inhibition by the substrate analogues (R)-2-dodecanoylaminohexanol-1-phosphocholine and its phosphoglycol derivative was tested on zwitterionic micelles as substrate. Group IIA PLA(2) shows a preference for the phosphoglycol inhibitor whereas the phosphocholine inhibitor binds stronger to the active site of group V PLA(2). The enzymatic activity was also measured on zwitterionic liposomes which appear to be much better substrates for group V PLA(2) than for group IIA PLA(2). The overall results suggest that group V PLA(2) is better suited for action on biological membranes than group IIA PLA(2).

Deterioration of sperm quality in young healthy Belgian men

We have retrospectively analysed the sperm characteristics of 416 consecutive healthy young men who presented themselves in the past 19 years as candidate sperm donors. Ejaculate volume increased slightly (P = 0.067), and average sperm concentration decreased (P = 0.035) by 12.4 x 10(6)/ml over the observation period, so that sperm count per ejaculate remained unchanged (P = 0.91). In contrast, sperm morphology (r = - 0.23, P < 0.0001), rapid progressive motility (r = - 0.42, P < 0.0001) and total motility (r = - 0.33, P < 0.0001) presented an important and time-related decrease. When a quadratic model was used rather than a linear one to analyse the data on rapid progressive motility, there appeared to have been no further decline since 1990. The average proportion of spermatozoa with normal morphology decreased from 39.2% in the period 1977-1980 to 26.6% in 1990-1995 (P < 0.0001), and the mean percentage of spermatozoa with rapid progressive motility decreased from 52.7 to 31.7% (P < 0.0001). The percentage of candidate donors with sperm characteristics below the 5th percentile cut-off value of a normal fertile population increased from 13 to 54% during the observation period (P < 0.0001). Since the technique of semen analysis has remained essentially unchanged in-so-far as has been practically possible, as has the method of recruitment of candidate sperm donors, the observed deterioration of sperm characteristics is considered to reflect degeneration of sperm production among men aged between 20 and 40 years.

Statement on the general reduction in sperm quality

Over a period of 17 years, 360 young healthy men presented themselves as candidate donors for the sperm bank of the University Hospital of Ghent. Semen characteristics of these men were assessed using unaltered methods, and analysis was performed on the first sample delivered before any donor selection was performed. Sperm motility and morphology, but not the total sperm count per ejaculate, exhibited a highly significant decrease. Over 40% of candidate donors since 1990 exhibited subnormal sperm characteristics, as against only 5% of the group investigated before 1980.

Androgens in seminal plasma: markers of the surface epithelium of the male reproductive tract

Androgens in seminal plasma have been investigated in relation to other markers of the male reproductive system. Testosterone and dihydrotestosterone (DHT) were measured by radioimmunoassay after paper chromatography in 104 semen samples. Concentrations of testosterone and DHT were significantly lower in samples from patients with abnormal sperm characteristics than in men with normozoospermia. Both testosterone and DHT were correlated significantly with sperm concentration (r = 0.40, p < 0.001; r = 0.41, p < 0.001, respectively), motile sperm concentration (r = 0.35, p < 0.01; r = 0.35, p < 0.01) and ATP concentration (r = 0.59, p < 0.001; r = 0.45, p < 0.001). In addition, the total amounts of testosterone and DHT were correlated with total activity of alpha-glucosidase (r = 0.49, p < 0.001; r = 0.58, p < 0.01), and gamma-glutamyltransferase (r = 0.49, p < 0.001; r = 0.48, p < 0.001) in seminal plasma. Transferrin (Tf) concentration in seminal plasma was significantly lower in samples without spermatozoa, and total Tf content was lower in oligozoospermic samples (p < 0.05). Testosterone and DHT were correlated positively with Tf levels in seminal plasma (r = 0.48, p < 0.0001; r = 0.78, p < 0.0001 respectively). Testosterone, DHT and Tf in seminal plasma were higher in the first than in the second fraction of split ejaculates, and DHT, but not testosterone, increased significantly in each of six patients treated with tamoxifen. Testosterone, DHT, and Tf in seminal plasma were not correlated with serum concentrations of LH, FSH, testosterone or prolactin, but the DHT : T ratio in seminal plasma was correlated with serum LH (r = 0.36, p < 0.05). It is concluded that the concentration of androgens in seminal plasma is related predominantly to the activity of the seminiferous epithelium and, to a lesser extent, to the function of the accessory sex glands.

Human semen analysis

Rapid developments have occurred in the management of couple infertility due to a male factor. These have stimulated renewed interest in semen analysis, which has become more correct, more reliable and more informative. The so-called basic semen analysis, which includes subjective estimation of sperm concentration, motility and morphology, has largely become obsolete. It has been replaced by several alternative techniques such as the home testing of semen by the man himself, the elaboration of methods and equipments for the exact assessment of conventional sperm characteristics, and the measurement of new parameters evaluating the functional state and capacity of spermatozoa, accessory sex glands and seminiferous epithelium. The present paper covers the following items: (i) conventional methods of semen analysis, (ii) the resazurin test and home fertility scoring, (iii) advanced methods for the objective assessment of conventional sperm characteristics and motility parameters.

Comparison of different methods for the investigation of antisperm antibodies on spermatozoa, in seminal plasma and in serum

Since there is no gold standard for the diagnosis of immunological infertility, comparison between different methods and of their results with biological tests for the detection of antisperm antibodies must be used in defining the most reliable and clinically relevant method. We have evaluated the results of direct (n = 100) and indirect tests in serum (n = 140) and seminal plasma (n = 100) using the SpermMAR and Immunobead (IB) techniques for the detection of sperm antibodies of the immunoglobulin (Ig) classes G, A and M, and we have compared the results with those of the tray agglutination test and the adenosine triphosphate release cytotoxicity test. Results indicate the higher specificity and sensitivity of the SpermMAR results for IgG and IgA, as compared to the outcome of the IB test. It appears that the IB test for IgA may detect non-specific antibodies in serum. Little information is obtained from the tray agglutination test in seminal plasma, and the indirect SpermMar test for IgG in seminal plasma was the only independent variable associated with the outcome of the former test. Since the SpermMAR tests for IgG and IgA are more accurate and biologically relevant, as well as easier to perform than the respective IB tests, the former must be considered the method of first choice.

Methodological aspects of sperm morphology evaluation: comparison between strict and liberal criteria

OBJECTIVE

To compare the methodological accuracy of different sperm morphology criteria.

SETTING

A multicenter study including 10 laboratories with high expertise in semen analysis.

PATIENTS

Semen preparations of subfertile men with a variable degree of teratozoospermia and of fertile semen donors.

INTERVENTIONS

Detailed assessment of sperm morphology on 10 air-dried semen smears, of which 3 originated from the same ejaculate.

RESULTS

The average coefficient of variation calculated on the three smears of the same ejaculate was higher when strict criteria for morphological normality were used and borderline cells were classified as abnormal than when criteria of abnormality were applied and borderline cells were considered normal. The correspondence between individual centers mutually and of each center with the average result of all centers was better when the latter approach was taken. The performance of two computer-assisted systems was intermediate between that of the two approaches, whereas one system gave unreliable results.

CONCLUSIONS

Strict criteria for normality of sperm morphology, with borderline cells considered abnormal, gives results that are less reproducible and less accurate than the approach that classifies sperm as abnormal, with borderline cells considered normal.

Comparison of the resazurin test, adenosine triphosphate in semen, and various sperm parameters

The results of the resazurin test (RES) and adenosine triphosphate (ATP) concentration in semen, measured by two methods, were compared for their ability to predict sperm parameters of semen samples from 42 subfertile men as assessed by a semi-computerized system. The highest correlation of RES grade was with sperm concentration (r = 0.70, P < 0.001), concentration of motile spermatozoa, concentration of motile spermatozoa with normal morphology and the ATP concentration using the reference LKB method (all r = 0.65, P < 0.001). The RES test has a positive predictive value of 93% for a progressive motile sperm concentration of 20 x 10(6)/ml or more, and a negative predictive power of 90% for the same variable at a criterion value of 10 x 10(6)/ml. The results of ATP measurement using the reference LKB and FireZyme methods presented a strong correlation (r = 0.74, P < 0.001). The correlations between ATP measurements from the FireZyme method and sperm characteristics were better than those obtained using the reference LKB method for ATP determination. It is concluded that the RES test can be performed with a relatively small volume of semen; it is easy to perform and requires not technical equipment. The accuracy and predictive value of this test are similar to more sophisticated ATP measurements. In addition, the RES may identify a subgroup of subfertile men with a decreased reducing capacity of semen.

Comparison between cell motion analyser, autosperm, and conventional semen analysis

With the aim of explaining some of the controversy on the value of computer-assisted methods of semen analysis, a study was conducted comparing the fully automated cell motion analyzer (CMA), the semi-computerized autosperm system (AS) and the conventional manual method. The CMA equipment gave higher values for sperm concentration than the mean of the three methods. Sperm concentration estimated with the conventional method was below the average of the three methods. The conventional method overestimated sperm motility, which was underestimated by CMA. The correlation between sperm velocity characteristics estimated by CMA and AS was significant, but only 18% of variability of one method could be explained by variability of the other. The reasons for the discrepancy between velocity measurements in the two methods are discussed in relation to possible shortcomings in sperm paths smoothing using the CMA method and the effect of technician training in the AS method. The AS method was found to provide more reproducible results which correlated better with those of the manual method as recommended by the World Health Organization.